This invention relates to the retaining of a canvas stretcher frame within a picture frame, and more particularly to a universal clip for use in conjunction with decorative picture frames having a canvas stretcher frame receiving rabbet grooves of varying depths for retaining the stretcher frame in the picture frame.
A substantial amount of artwork, such as those which use oil paints as a medium, is applied directly on a canvas backing which is stretched tautly about a stretcher frame. The prior art has used small nails or brads driven into both frame members, or other similar means where the rabbet groove in the picture frame is shallow relative to the stretcher frame such that the rear surface of the stretcher frame extends above the rear surface of the picture frame. In those cases where the picture frame has a deep rabbet such that the rear stretcher frame is at the same or lower level as the rear of the picture frame, brads or small metallic triangular tabs such as glazier tabs have been used. In all these cases extreme care must be exercised in the attachment process or damage to the frame members can readily occur. Additionally, if one marketing canvas artwork were desired to display the work in a frame which is not sold with the artwork, or would like to temporarily mount the work in different frames for showing a customer how the work will appear in a number of other frames, these prior art mounting means are not practical.
One solution to some of the deficiencies in this prior art is proposed in Moede U.S. Pat. No. 4,027,413 which discloses a clip having a main body of a rectangular form having a first leg having a pair of points at one end for engaging the rabbet groove of the picture frame between the adjacent walls of the rabbet and the edge of the stile or rail of the stretcher frame, and a second leg that resiliently engages the other edge of the same stile or rail, the main body being disposed on the rear surface of the stile or rail. The disadvantage of this clip is that it only functions in those situations where the rear face of the stile or rail of the stretcher frame extends beyond the rear face of the picture frame, i.e., the rabbet groove is shallow relative to the front to rear thickness of the stretcher frame. This clip is not functional where the picture frame has a deep rabbet groove relative to the thickness of the stretcher frame, such as those picture frames having a highly decorative carved configuration. The reason for this is because the body of the clip must be rotated about the points of the first leg over the stile or rail to move the second leg into frictional engagement with the remote edge of the stile or rail, and since this requires leverage to be applied on the points with the remainder of the leg acting as a lever, no surface is available in a deep rabbet groove for the first leg to function as a lever so that the second leg cannot be rotated to engage the remote edge of the stretcher frame. Since the stiles and rails of stretcher frames have standard widths, this prior art clip is not universally applicable for use with all picture frames, i.e., they cannot be used with picture frames having deep rabbet grooves.